This is the mail archive of the systemtap@sourceware.org mailing list for the systemtap project.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]
Other format: [Raw text]

Re: [PATCH v3 2.6.39-rc1-tip 6/26] 6: Uprobes: register/unregister probes.


> > +
> > +		mm = vma->vm_mm;
> > +		if (!valid_vma(vma)) {
> > +			mmput(mm);
> > +			continue;
> > +		}
> > +
> > +		vaddr = vma->vm_start + offset;
> > +		vaddr -= vma->vm_pgoff << PAGE_SHIFT;
> 
> What happens here when someone passes an offset that is out of bounds
> for the vma?  Looks like we could oops when the kernel tries to set a
> breakpoint.  Perhaps check wrt ->vm_end?
> 

If the offset is wrong, install_uprobe will fail, since
grab_cache_page() should not be able to find that page for us.
And hence we return gracefully.

I will surely test this case and I am happy to add a check for
vm_end.

-- 
Thanks and Regards
Srikar


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]